Apps in this Guide

Wise Registry Cleaner

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CCleaner

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Registry First Aid

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A registry cleaner is a tool for Windows computers that attempts to tidy up the entries in the Windows Registry, which can get messy over time. The registry is a kind of map that tells the operatingmore

A registry cleaner is a tool for Windows computers that attempts to tidy up the entries in the Windows Registry, which can get messy over time. The registry is a kind of map that tells the operating system where your software is installed, how to run that software, and what physical components are inside your computer.

The basics of a registry cleaner

Among other tasks, this utility looks at the application locations listed in the registry and checks to see if those programs are still present in their folders. Sometimes these registry entries remain after you've uninstalled a program. Low-level application settings may also remain -- these need to be removed to actually complete the uninstallation process.

Other precautions to take

A registry cleaner is a low-level utility and requires your understanding a bit about what it's doing, because a mistake at the lower level can be costly. Go lightly, and don't be afraid to research a term if the cleaner uses mysterious jargon.

Not all registry cleaners are safe

Sometimes the cleaner will remove an entry for something that it shouldn't. This overly aggressive cleaning method can cause an application to not run, or to crash unexpectedly. Or Windows itself may start behaving strangely. Therefore, you should always create a backup copy of your Windows registry before editing it, and before letting any automated tool clean it for you.

To create a backup copy, press the Windows key, type "regedit," and press the Enter key to open the registry editor. Then click the File menu in the upper left, select Export, choose a name for your backup copy, and click the Save button. By default, this copy is saved to your desktop. We recommend putting it on an external storage device, such as a USB thumb drive.

The most effective method of recovering from overly aggressive changes to the registry is to create a backup copy of the storage device that Windows is installed on.

Recommended Registry Cleaners

Wise Registry Cleaner

Wise Registry is one of the few free Registry cleaners that you'll see get consistently recommended. It can backup and restore the Registry, clean according to a schedule, employ different cleaning levels, and create a Windows Restore Point before changing anything, to reduce the chance of the operating system being rendered unusable.

CCleaner

CCleaner is great at automating a lot of file cleanup activities, though we'd dial back its aggressiveness toward tidying up your browser cache and the Windows registry. A browser cache is useful for quickly reloading previously visited Web pages. And since it's a cache, it will just get gradually refilled if you delete all of its contents, so space savings is pretty temporary. CCleaner is also good because it works with older versions of Windows all the way back to XP, and it's frequently updated.

Registry First Aid

Unfortunately, free registry cleaners don't have a great reputation. Their interfaces can be confusing, or they may encourage you to clean everything in one click, which is just asking for trouble. A cleaner such as Registry First Aid avoids such pitfalls and even has built-in backup and restoration features. A license is $28, but you can try it for free.